When using the bucket, you push the lever all the way up until you reach the desired height. Then you lower the lever until it clicks which stops the rise. You need the hydraulics set for lift and hold to get the desired action. If you have the decals on the battery box, they should explain it. The other manuals do as well.
I read your post again. Maybe I am missing something.
If your cylinders can get bent, the cylinders are too long. These cylinders should reach the end of stroke before you bend them.
I'd have to see the lift frame to venture a guess on how to straighten it.